They may use Exclusive weld pins with integral-cupped head washers. Unfaced boards can then be completed with strengthened insulating cement, canvas, or weatherproof mastic. Confronted boards could be installed in precisely the same way, as well as the joints between boards sealed with tension-delicate tape or glass material and mastic. https://freeecogrants.co.uk/how-to-make-your-home-comfortable-through-eco-grants/